Nestled in the forest above Skreia, across Mjøsa from lillehammer, my hytte is awash in eerie bluish midnight sun. Although the hytte lies below the artic circle and in the shadow of the earth at midnight, the eye's high dynamic range easily perceives visible EM radiation turned a ghostly hue by Rayleigh scattered rays high in the atmosphere. Even my chintzy digital camera is up to the task, provided sufficient exposure time.
Photographs taken on the moon display a quality of shadow strange to the human eye. No apparent gradient exists between bright and dark; devoid of atmosphere, the sky is black and does not provide diffusion necessary to illuminate shadows. Without atmosphere, my hytte would be shrouded in darkness after sunset.
Unfortunately, EM radiation in the frequencies used by Telenor for HSDPA and UMTS is less amenable to diffusion by water vapor and atmosphere than visible light. In these spectra, the surface of the earth resembles the moon: dark shadows dwell wherever terrain obscures the EM radiation from cellular towers. Looking closely, perhaps the faintest glimmers reflect from the sides of hills into valleys. In a valley, a cellphone would indicate that inadequate 3G service exists - enough for one to know to climb a hill for better reception.
I receive precisely this indication by the dining room windows of my hytte. The service by the window is adequate to transfer at just 5KiB/s; no signal penetrates further into the hytte.
Placed in a ziplock bag tied to a stick that is attached to the end of a ladder resting against the front of the hytte, my 3G modem is well enough outside of the terrain shadow to perform satisfactorily.
A USB extension cable connects the modem to my laptop.
My laptop performs NAT for the rest of the network, including my portable XPC workstation.
Labels: electromagnetic propagation, hytte
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